Pneumatic percussive tool.



C. H. HAESELER. PNEUMATIC PERCUSSIVE TOOL, APPLICATION FILED MAR. 20. I911.

' 1,240,709 PatentedSept. 18,1917.

2 SHEETS-SHEET I.

$35 N Mx -n 1 w w I \mr ATTORNEYS C. H. HAESEL-ER.

PNEUMATIC PERCUSSIVE TOOL.

APPLICATION man MAR. 20. ran.

1,240,709. Patented Sept. 18,1917.

2 SHEETS-SHEET 2.

04 4/11/5 zz F/616 CHARLES H, HAESELER, OF PHILADELPHIA, PENNSYLVANIA.

PNEUMATIC PERCUSSIVE TOOL.

Specification of Letters Patent.

Patented Sept. 18, 191?.

Application filed (March 20, 1917. Serial No. 155,996.

1 "0 all whom it may concern:

Be it known that I, CHARLES H. HAESELER, a citizen of the United States, residing in the city and county of Philadelphia, Stateof Pennsylvania, have invented a new and useful Pneumatic Percussive Tool, of which the following is a specification.

In a co-pending application filed by me on the 29th day of March, 1915, Serial No. 17,751, I have described and broadly claimed a novel construction of a pneumatic percussive tool, wherein means are employed to retain the working tool, such as for example, a rivet set or chisel, beyond the range of the hammering piston, to thereby not only prevent injury to the working tool and to the piston and cylinder, but also to prevent the working tool from being accidentally disengaged from the cylinder of the percussive too f In a large number of States in this country and also in many foreign countries, laws have been passed rendering it compulsory to provide in conjunction with devices of this character, means to prevent the working tool from becoming accidentally removedfrom 'its association with the cylinder with consequent likelihood of injury to anyone in the path of the working tool or the hammering Diston if they are discharged from the cylinder.

With the above in view, my present invention consists of a percussive tool wherein means are rovided to pass fluid pressure to the working tool to retain it beyond the range of the stroke of or beyond the path of the piston.

'It further consists of a novel construction of a tool retainer and novel means for interlocking it with respect to the cylinder of the percussive tool.

It further consists of a novel construction of a cylinder adapted to receive a working tool, novel means to limit the outward travel of the working tool, and novel means to pass motive fluid to the working tool. o

Other novel features of construction and advantage will hereinafter more clearly appear in the detailed description of my invention.

For the purpose of illustrating my invention, I have shown in the accompanying drawings typical embodiments thereof which are at present preferred by me, since the same will give in practice satisfactory and reliable results, although it is to be understood that the various instrumentalities of which my invention consists can be variously arranged and organized and that my invention is not limited to'theprecise arrangement and organization of these instrumentalities as herein shown and described.

Figure 1 represents a sectional elevation of a pneumatic percussive tool embodying my invention.

Fig. 2 represents a sectional elevation similar to Fig. l, but showing certain of the parts in a difi'erentrelation from that seen in Fig. 1.

Fig. 3 represents a plan view of the forward end of the tool.

Fig. at represents a top plan. view of the tool retainer in detached position.

Fig. 5 represents a section on line 55 of Fig. 4:.

Fig. 6 represents, in side elevation, the forward end of a percussive tool, which is similar to that seen in Figs. 1, 2 and 3, the retaining sleeve being indicated in dotted lines.

Fig. 7 represents a section on line 7-7 of Fig. 6.

Fig. 8 represents, in side elevation, another embodiment of my invention, in which the construction is similar to that seen in the other figures, except that the forward end of the cylinder of the percussive tool is not reduced in diameter.

Similar numerals of reference indicate corresponding parts in the figures.

Referring to the drawings My present invention is directed to that class of percussive tools, wherein a hammering piston is reciprocated by motive fluid and imparts its blow to a working tool and is designed to be employed in conjunction with tools of the chipping type, wherein the stroke of the reciprocating piston is less than its own length, and also in percussive tools of the riveter type, wherein the stroke of the piston is greater than its own length, it being understood that my invention may be employed in all cases wherein a working tool is to be retained in position.

In accordance with my present invention, I utilize the motive fluid to maintain the working tool beyond the range of stroke of or beyond the path of the piston, and it is therefore necessary for a clear understanding of my'invention to describe in general the cycle of the operation. I have therefore.

illustrated the main distribution valve, the

hammering piston and the ports and passages for the motive fluid, which cooperate with said main distribution valve and piston, as conforming to the construction described and broadly claimed in my co-pending application for pneumatic percussive tool, which was filed by me on the 12th day of May, 1916, and received a Serial No. 97,014, and to which reference may be had, it a description more in detail of the construction is desired. 1t is, however, to be understood that any desired type of distribution valve and any desired arrangement of the ports and passages controlling th piston may be employed.

1 designates a barrel or cylinder of a pneumatic percussive tool embodying my invention, said cylinder having its rear end open and adapted to enter the head block 2 of the handle 8, which is provided with a grasping portion 4:. The handle is secured with respect to the cylinder 1 by means of a fastening device 5. 6 designates a throttle valve lever, which controls the passage of live motive fluid to the passage "1 leading through the grasping portion 4 of the handle, said passage 7 communicating with the chamber 8 of the main distribution valve 9. The main distribution valve 9 is provided with a desired number of inlet ports 10 and 11 which communicate respectively with opposite ends of a valve chamber 12, in which is located a valve 13, which for purpose of illustration is shown as being of the ball type.

14 designates a passage communicating with the valve chamber 12 and with the rear end of the piston chamber 15, and 16 designates a passage communicating with the valve chamber 12 and with the forward end of the piston chamber 15. The cylinder 1 is provided with exhaust ports 17 leading to the atmosphere. 18 designates the hammering piston which consists of a cylindrical bolt having a forward extension or striker 19 of reduced diameter, and which forms the impact or striking'portion of the piston. The piston chamber 15 communicates with an aperture 20 of reduced diameter, thereby forming a shoulder 21, and through this aperture 20, the striker 19 is adapted to freely pass in order to impact against a shank 22 of a working tool 23, which in the form illustrated consists of a rivet set, although, as is apparent, the operative end of the workingtool may have any desired contour in order to adapt it for the work to be accomplished.

V The aperture 20 communicates with the aperture or bore 2 1, which opens through the forward end of the cylinder 1, and the shank 22 of the working tool 23 preferably has a working fit in the aperture 24. In the embodiment seen in Figs. 1, 2, 3 and 6, the forward end of the cylinder 1 is turned macros off, as indicated at 25, thereby forming a shoulder 26, and on this cylindrical portion 25, a desired distance from the shoulder 26, are formed a desired number of lugs, 27, and in the present instance, 1 have illustrated three of such lugs. The rear faces of these lugs 27 are recessed to form a seat 28, the bottom portion of which is, preferably substantially flat and merges into the curved sides 29, as will be best understood by reference to Figs. 6 and 7.

30 designates a tool retainer which con sists of a cylindrical sleeve having its forward end provided with or formed with an inwardly extending flange 31, the inner wall of which is preferably beveled, as indicated at 32, in order to engage the beveled wall 33 of a flange 34 on the rivet set 23. The tool retainer 30 has an aperture 35 through the flange 31, and this aperture communicates with the bore 36, which is of such internal diameter as to form a proper working lit with the forward end er the rivet set 23. The bore 36 communicates with the bore 37, which is of greater internal diameter than the bore 36 and opens through the rear end or the retainer 30. At the rear end of the retainer 36, internal lugs 38 are provided, which project into the bore 3? and are shaped to conform to the seat 27 on the cylinder 1. shown, each. of these lugs 38 has its forward "face substantially fiat and is provided with rounded sides 40 designates a spring, preferably constructed of rectangular material to form a helical spring which is contained within the bore 3?. The outer face of the tool retainer 30 near its rear end converges forwardly, as indicated at 11, and its periphery is preferably knurled, in order that it may be the: more readily grasped by the hand of the operator.

In the embodiment seen in Fig. 8, the construction is similar to that just described, except that instead of reducing the diameter of the cylinder at its forward end, a cylinder 42 is provided of which the external diameter is unchanged and lugs 43 are formed on the outer periphery of the cylinder, such lugs corresponding in construction and function to the lug forming seats 27. The other parts are similar to those already described, and I have therefore given to corresponding parts similar reference characters, it being understood that the only dii'i'erence in the tool retainer would be that the bore 37 would be of somewhat greater internal diameter than it would be in case the forward end of the cylinder was turned OH or of reduced external diameter.

When it is desired to assemble the tool retainer and tool with respect to the cylinder, the working tool is passed into the tool retainer, the flange 31 coiiperating with the shoulder 34 to limit such movement.

The tool retainer is then moved rearwardly on the cylinder 1, the lugs 38 passing between the spaced seats 27, and the tool retainer is then partially turned to bring the lugs 38 into alinement with the seats 27. The spring 40 which has been compressed as the tool retainer is moved rearwardly into position serves to resiliently retain the lugs 38 in engagement with their seats 37 so that the working tool 23 cannot be removed until the lugs 38 have first been moved out of alinement with the seats 27 and the tool retainer 30 removed from the cylinder 1.

In the cycle of the operation, assuming that the throttle valve lever 6 is depressed, live motive fluid passes through the passage 3 in the grasping portion 4: of the handle 3, and into the chamber 8. Assuming that the parts are in the position seen in Fig. 2, live motive fluid passes from the chamber 8 through the ports 10 into the valve chamber 12 thence through passage 14 into the piston chamber 15 in rear of the piston 18 and causes the latter to move forwardly. The striker 19 passes through the aperture 20 and impacts against the shank 22 of the working tool 23, the exhaust taking place through the exhaust ports 17. As soon as the piston passes'the ports 17 on its forward movement, the motive fluid can exhaust through such ports into the atmosphere, thereby reducing the pressure in rear of the valve 13,and such valve then moves from its position seen in Fig. 2 into that seen in Fig. 1. Live motive fluid may now pass from the chamber 8 through the ports 11 into the valve chamber 12 and therefrom through the passage 16 and into the forward end of the piston chamber 5, and exerts its pressure on the pressure area formed by the shoulder of the piston 18 and causes the piston to move rearwardly' As soon as the shoulder formed by the striker 19 and the body of the piston passes the exhaust ports 17, live motive fluid is free to exhaust into the atmosphere and the pressure is reduced in front of the valve 13, thereby causing the valve to change from its position seen in Fig. 1 into that seen in Fig. 2. The cycle of the operation just described is then repeated.

The striker 19 has a loose fit in the aperture or bore 20, so that the motive fluid passes around the striker 19 into the chamher 24 in rear of the shank 22, thereby causing the working tool 23 to be retained in its ficiently to cause the working tool to contact with the work, the working tool will assume the position seen in Fig. 2, so that the blows of the hammering piston will be imparted to the working tool.

Owing to the provision of the shoulder 2 it will be impossible to discharge the piston through the forward end of the cylinder and such piston can only be removed from the cylinder by first removing the handle 2, as is evident.

It will be seen that the tool retainer is supported on the exterior of the forward end of the percussive tool and is adapted to loosely hold the working tool in association with the hammer. I provide fluid pressure means for holding the tool in advance position beyond the range of the piston after the first blow of the piston when the percussive tool is not in proper working position and the tool retainer limits the forward travel of the working tool.

Special attention is directed to the feature of providing means to limit the forward stroke of the piston whereby the piston is prevented from being ejected from the forward end ofthe percussive tool and its forward stroke is positively limited so that when the working tool is retained by fluid pressure means beyond the range of the working stroke of the piston it cannot impact against the shank of the working tool, when the percussive tool is not held in proper working position.

As soon, however, as the tool is pressed toward the work the relationship between the reciprocatory piston and the working tool will be such that the piston will impact against the inner end of the shank of the working tool. By such construction, I not only provide means which positively prevents the piston from being ejected from the cylinder of the percussive tool but I also provide means whereby the working tool when it is not pressed against the work is retained in its forward advanced position and out of range of the hammering piston.

From the foregoing disclosure, it will be apparent to those skilled in this art that the live motive fluid which passes to the forward end of the piston chamber to return the hammering piston to its initial or starting position at the rear end of the cylinder is utilized during the return stroke of the piston to maintain the working tool in its advance position beyond the range of the piston.

During the forward stroke. of the piston, as soon as it passes the exhaust ports 17, compression of motive fluid is present between the piston and the working tool so that during such period in the forward stroke of the piston, the working tool is maintained in its advance position beyond the range of the piston by compression of motive fluid between the piston and the working tool.

It will thus be apparent that in accordance with my present invention there is no likelihood of the workingtool, its retainer or the piston becoming accidentally removed from the tool, thereby enabling one to elimi nate the possibility of injury to workmen or others in the vicinity of the work, such as frequently, occurs in cases wherein the tool is not constructed in such a manner that the above mentioned parts are incapable of be: ing accidentally removed due to the improper handling of the tools by careless or ineflicient workmen.

It will now be apparent that I have de-' vised a novel and useful pneumatic percus- 'sive tool which embodies the features of advantage enumerated as desirable in the statement of the invention and the above description, and while I have, in the present instance, shown and described typical embodiments thereof which will give in practice satisfactory and reliable results, it is to be understood that these embodiments are susceptible of modification in various particulars without departing from the spirit or scope of the invention or sacrificing any of its advantages.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is i 1. The combination with a pneumatic per- I cussive tool having a reciprocating iston,

of a working tool adapted to receive t e impact of said piston, and means to pass motive fluid to said working tool to retain it beyond the range of said piston when the percussive tool is not in proper working position. 4 I

2. The combination with a pneumatic percussive tool having a reciprocating piston, of a working tool adapted to receive the impact of said piston, means to pass motive fluid to said working tool to move it beyond the range of the piston when the percussive tool is not in proper working position, and means to limit the extent of such movement of the working tool.

3. The combination with a fluid pressure operated percussive hammer and its working tool, of a tool retainer supported on the exterior of the forward end of the hammer and adapted to loosely hold the tool in association with the hammer, said working tool being retained in its advance position beyond the range of the piston after the first blow of the piston when not in proper working position solely by the use of motive fluid.

4. The combination with a fluid pressure operated percussive tool and its working tool, of a tool retainer comprising a sleeve supported by the exterior of the forward end of the percussive tool and adapted to loosely hold the working tool in association with the percussive tool, said sleeve having means to limit the forward movement of the cussive tool when the latter is not in working position, and means to pass motive fluid to said working tool to retain it in advanced position beyond the range of the percussive tool when the latter is not in proper working position.

5. The combination with a fluid pressure operated percussive tool and its working tool, of a tool retainer for holding the working tool in association with the percussive tool, the working tool being freely slidable in said retainer and free to vibrate therein, said retainer having means to limit the forward movement of said working tool, and means to pass motive fluid to the working tool to retain it in advanced position beyond the range of the percussive'tool when the latter is not in proper working position.

6. The combination with a fluid pressure operated percussive tool and its working forward movement, and fluid pressure means to retain said working tool in its advanced position beyond the range of said percussive tool when the latter is not in proper working position.

8. The combination with a pneumatic percussive tool having a cylinder provided with lug forming seats at its forward end, of a tool retainer comprising a sleeve having means to engage said seats, a spring to retain said means in engagement with said seats, a working tool within said sleeve and having means cooperating with said tool retainer to limit its forward movement, and fluid pressure means to retain said working tool in its advanced position beyond the range of said percussive tool when the latter is not in proper working position.

9. The combination with apneumatic percussive tool having a cylinder provided near its forward end with spaced lugs, of a tool retainer comprising a sleeve adapted to receive the end of said cylinder and provided with lugs adapted to pass between the cylinder lugs and seat thereon, a spring within said retainer to maintain said lugs in encylinder, said working tool having means thereon cooperating with the retainer flange to limit the movement of said working tool in one direction and permit its free movement in an opposite direction, and means to retain said' Working tool in its advanced.

position by fluid pressure when said worklimited movement through the forward end thereof, and means to retain said working tool beyond the range of the percussive tool when the latter is not in proper working position. v

11. The combination with a pneumatic percussive tool having a cylinder provided with a bore of different internal diameters, a piston reciprocable in one of said bores and 'having a striker loosely fitting an adjoining bore, a working tool adapted to enter the other of said bores, means cooperating with said cylinder and working tool to limit the forward movement of the latter, and means to introduce motive fluid to actuate said piston and thereby to act against the rear end of said working tool to retain it beyond the range ofsaid piston when the percussive tool is not in proper working position.

12. The combination with a pneumatic percussive tool having a cylinder and a re ciprocatory piston and a piston chamber to receive said piston, of a working tool to receive the impact of said piston, means to loosely hold said working tool 1n assoc1at1on with said cylinder and to limit its forward movement, and means to cause motive fluid to pass from said piston chamber to act on said working tool and retain it in its advanced position beyond the range of the-piston when said percussive tool is not in proper working position.

13. A pneumatic percussive tool having a reciprocatory piston and a cylinder to receive said piston and having means to prevent said piston being ejected from its forward end, of a working tool to receive the impact of said piston, and fluid pressure means to retain said working tool beyond the range of said piston when the percussive tool is not in proper working position.

14. A pneumatic 'percussive tool having a reciprocatory piston and a cylinder to receive said piston and having means to prevent said piston being ejected from its forward end, of a working tool to receive the impact of said piston, fluid pressure means to retain said working tool beyond the range of said piston when the percussive tool is not in proper working position and. to loosely hold said working tool in association with said cylinder.

15. A pneumatic percussive tool having a cylinder provided with a differential bore forming an internal shoulder at its forward end, a diflerential piston said bore and having its forward travel limited by said shoulder, a working tool to receive the impact of said piston, "means to loosely hold said working tool in association with said 17. A pneumatic percussive tool having a reciprocatory piston and a cylinder to receive said piston and having an internal shoulder near its forward end to prevent said piston being ejected from its forward end, of a working tool to receive the impact of said piston, and means to utilize the fluid pressure acting against the piston to retain said working tool beyond the range of said piston when the percussive tool is not in proper working position.

18. A pneumatic percussive tool having a cylinder provided with a differential bore forming an internal shoulder atits forward end, a differential piston in said bore and having its forward travel limited by said shoulder, a working tool to receive the impact of said piston, means to loosely hold said workin tool in association with said cylinder an to limit its forward movement, and means to utilize the motive fluid which effects the return of said piston' to retain said working tool beyond the range of the piston.

19. The combination with a fluid pressure operative percussive tool and its working tool, of means for holding said working tool in association with said percussive tool, said working tool being retained in its advance position beyond the range of the percussive tool by live motive fluid and compressed motive fluid.

20. The combination with a fluid pressure operative percussive tool, its piston, and its working tool, of means for holding said working tool in association with said percussive tool, said workin tool being retained .in its advance position beyond the ran e of the piston during the rearward stro e of the latter by live motive fluid and during the forward stroke of the piston by compressed motive fluid.

21. The combination with a fluid pressure operative percussive tool, its piston, and its working tool, of means for holding said working tool in association with said percussive tool, said working tool being retained in its advance position beyond the range of the piston during the forward stroke of the latter by compression between the piston and the working tool and during the rearward stroke of said piston by the live motive fluid which eiiects the return stroke of said piston.

22. The combination with a fluid pressure operative percussive tool and its working tool, of a tool retainer supported on the exterior of the forward end of said percussive tool and adapted to loosely hold the working tool in association with the percussive tool, said working tool being retained solely by fluid pressure in its advance posi tion beyond the range of the piston when the percussive tool is not in proper working position.

23. The combination with a fluid pressure operative percussive tool, its piston, and its working tool, of means for holding said working tool in association-with said percussive tool, and-means to utilize the live motive fluid which returns the piston to its initial position to maintain the working tool in its advance position beyond the range of the piston, said working tool being maintained in its advance position beyond the range of the piston during the forward stroke of the piston by compression of motive fluid between the piston and'the working tool.

24:. The combination with a fluid pressure operative percussive tool, its piston, and its working tool, of a tool retainer for holding said working tool in association with said percussive tool, said working tool being freely slidable in said container and free to vibrate therein, said retainer having means to limit the forward movement of said working tool, and means to utilize live motive fluid durin the rear stroke of the piston to retain said Working tool in its advance position beyond the range of the piston said working tool being retained in its advance position beyond the range of the piston during the forward stroke of the latter by compression between said piston and said working tool.

CHARLES H. HAESELER.

Witnesses:

H. S. FAHIBANKS, C. D. MoVAY. 

